Currently, when it is necessary to completely remove a disc from between adjacent vertebrae, the conventional remedy is to fuse the adjacent vertebrae together. More recently, there have been important developments in the field of disc replacement, namely disc arthroplasty, which involve the insertion of an artificial intervertebral implant into the intervertebral space between adjacent vertebrae, and which allows limited universal movement of the adjacent vertebrae with respect to each other.
In conjunction with the development of such artificial intervertebral implants, instruments for inserting same were also developed. Such instruments are shown in Published Application No. WO 01/19295, published Mar. 22, 2001. An artificial intervertebral implant which was developed for use with said instruments is shown in Published Application No. WO 01/01893, published Jan. 11, 2001.
While the new instruments, methods and the artificial intervertebral implant shown in these publications represent a substantial improvement in the art, there exists a continuing need for improvements in the field of instruments and methods for inserting artificial intervertebral implants, especially in conjunction with newly developed artificial intervertebral implants.
One such area in need of further improvements includes instruments and methods for inserting artificial intervertebral implants into the cervical spine. This is because the cervical spine and the dimensions of the intervertebral spaces between the vertebrae are quite small. For example, the area of facing adjacent cervical vertebral surfaces may be only about 20% of the facing surfaces of the vertebrae in the lumbar region, thereby making this an extremely delicate area in which to insert an intervertebral implant.